A stop device is described and shown in German Utility Model 81 35 734. When working on narrow workpieces, the auxiliary stop ledge is swung into its operating position in which it rests on the machine table, whereby small disk-shaped feet serve as spacers between the auxiliary stop ledge and the machine table. In this operating position of the auxiliary stop ledge there is no danger of the hands of the operator slipping off the workpiece and being injured by the plane knife. On the other hand, if high workpieces are to be worked, for instance for the dressing of the narrow sides of boards, the auxiliary stop ledge must be swung into its ready position. In this ready position the auxiliary stop ledge is arranged behind and above the stop plate in the known device.
The known stop device is fully functional when the stop plate is in a vertical position. However, if it is necessary to bring the stop plate into an oblique position, for which purpose its back is fastened to a suitable holding and displacement mechanism, it cannot be avoided in most cases that the auxiliary stop ledge strikes against the upward protruding holding and displacement mechanism whereby it can be damaged; furthermore, in this ready position the holding and displacement mechanism cannot be actuated. Not least of all, in this oblique position the auxiliary stop ledge cannot be swung back sufficiently far, so that it extends into the path of movement of the workpieces thus rendering the working of high workpieces impossible.